1. Field of the Invention
The present invention relates to pipeline pigs and more particularly to a method and apparatus for transporting pipeline pigs, such as after they have been used to clean or scrape a section of pipeline. More particularly, the present invention relates to an improved pipeline pig transport method and apparatus that employs a housing having a specially shaped carriage that can be moved with a jack or jacking mechanism or elevator between collapsed and extended positions, the housing enabling transport of the contaminated pig after it has been removed and is covered with contaminants such as wax, oil, debris, dirt or the like.
2. General Background of the Invention
Pipeline pigs are often employed to clean a section of pipeline. A discussion of pipeline pigs can be found at www.ppsa-online.com/about-pigs.php.
Pig traps are used for inserting pigs into or removing pigs from a pipeline. The pig trap can be used for launching a pig or for removing a pig and without interruption of flow.
One of the inventor's customers invited him to look at a very crude device that was being used to assist the customer with pulling out pigs from pipelines that basically could only roll to the door of the pipe and then back away so the workers could close the door. This unit's feature was basically a trough with a hand winch which the operator cranked to pull the pig out. The liquids fell below in a container that was built in or part of the unit. After water was drained in the trough on site or overboard and liquids or oil were pumped out for proper disposal. The surface of the unit was basically grating that was bent to a concaved fashion to receive the pig. This unit was not portable for highway transport and also had no lid for protection of the pig nor did it have wind guards to prevent oils or residue from going into the environment. This unit did not retract the pig within itself and also was felt to be of great possible injury to the operator when removing the pig by cranking (as there was a risk of cable failure, which could injure the operator).
Patents have issued that relate to pipeline pigs and methods of handling them. Examples are in the following table. All references mentioned herein are incorporated herein by reference.
TABLEU.S. Pat. No./PublicationPublicationDateNo.TitleMM-DD-YYYY2,822,931Device for Loading Bombs and The Like02-11-19584,582,551Sealing Joints and Leaks with an Anaerobic04-15-1986Liquid4,643,855Sealing Joints and Leaks02-17-1987GB2196715Method Of Launching A Pig Into A Pipeline05-05-19885,044,827Method for Recovering Wet Buckled Pipe09-03-19915,178,429Pipeline Recovery Head01-12-19935,769,955Portable System for Launching/Catching06-23-1998Pipeline Pigs6,234,717Method and Apparatus for Connecting05-22-2001Underwater Conduits2001/0010782Method and Apparatus for Connecting08-02-2001Underwater Conduits6,503,021Method and Apparatus for Connecting01-07-2003Underwater Conduits2003/0026662Cable Installation02-06-20032004/0062630System and Methods for Handling Aircraft04-01-2004munitions6,767,165Method and Apparatus for Connecting07-27-2004Underwater Conduits6,925,671Pig Launcher08-09-20052007/0177944Apparatus and Method for Laying Down,08-02-2007Abandoning, and Recovering a Pipe on theSea Floor2009/0152520Pig Extracting Device06-18-2009
See also my United States Patent Application published Mar. 1, 2007 as US 2007/0045205 for Pipeline Pig Storage Rack Apparatus and my U.S. Pat. No. 7,588,644 issued Sep. 15, 2009 for Method and apparatus for cleaning pipeline pigs.